I had been running a whisper internal filter which made quite a bit of noise and the filters had to be changed every so often which for me at least always caused mini cycles and i lost fish.
Ive been running a canister filter for about 3 years and I will never go back to those internal filters. The canisters are virtually silent unless you're standing right next to them, you don't have to look at them in your tank, and the best part is once your bio system is set up you don't ever have to change the media. You only rinse it every 6 months to a year with tank water when you do a pwc
to clean out the accumulated gunk. I have been slacking lately and it's been quite a while since I've rinsed mine and I never have ammonia spikes or nitrite spikes [once the bio gets set up]
Look up some videos on YouTube on how quiet they can be. I have an eheim 2217 and 2211 which are fairly expensive but **** I love them. I bought mine from bigalsonline.com
The only downfall I think I've come in contact with is the amount of water that comes out of the return tends to push my sand and rock media around and when the power goes out it can be kind of a pain to get the water flowing again because it's mostly a gravity fed system, which is why they're so quiet lol
What kind of tank/fish do you have?